Educational device

ABSTRACT

A DEVICE FOR TEACHING THE EFFECTIVENESS OF THE PASSIVE TANK STABILIZER. A SMALL, LIGHTWEIGHT ARTICLE HAVING TWO OPPOSITELY POSITIONED ROCKER MEMBERS IS PARTIALLY FILLED WITH A STABILIZING MASS. WHEN PLACED ON ONE OF SAID ROCKER MEMBERS, THE DEVICE ROCKS TO AND FRO FOR A RELATIVELY LONG PERIOD OF TIME. WHEN, HOWEVER, THE ARTICLE IS PLACED ON ITS OTHER ROCKER MEMBER, IT ROCKS FOR ONLY A BRIEF PERIOD OF TIME, THUS DEMONSTRATING THE EFFECTIVENESS OF THE PASSIVE TANK STABILIZER.

S. B. FIELD ETAL EDUCATIONAL DEVICE Feb. 23, 1971 2 Sheets-Sheet 1 FiledMay '5, 1969 INVENTORS SHELDON B. FIELD, WILLIAM A. CRAGO BY I 4 7 mmhmw' ATTORNEYS 131x23, 1971 8, HELD y 3,564,133

EDUCATIONAL DEVICE Filed May 5, 1969- 2 FIG.5

2 Sheets-Sheet 2 I v I l SHELDON B. FlELD, WILLIAM A.' CRAGO INVENTORS'ATTORNEYS United States Patent O 3,564,733 EDUCATIONAL DEVICE Sheldon B.Field, Floral Park, N.Y., and William A.

Crago, Cowes, Isle of Wight, England, assignors, by

mesne assignments, to Flume Stabilization Systems, Inc.,

Hoboken, N.J., a corporation of New Jersey Filed May 5, 1969, Ser. No.821,647 Int. Cl. G09b 23/00 U.S. Cl. 3550 25 Claims ABSTRACT OF THEDISCLOSURE A device for teaching the effectiveness of the passive tankstabilizer. A small, lightweight article having two oppositelypositioned rocker members is partially filled with a stabilizing mass.When placed on one of said rocker members, the device rocks to and frofor a relatively long period of time. When, however, the article isplaced on its other rocker member, it rocks for only a brief period oftime, thus demonstrating the effectiveness of the passive tankstabilizer.

BACKGROUND OF THE INVENTION The passive tank stabilizer is well known;many years ago its basic principle was established. However, it was notuntil recently that this basic principle could be put to a practicaluse. Today, there are numerous ocean going vessels equipped with passivestabilization systems.

Presently, when it is the desire to demonstrate the effectiveness of apassive tank stabilization system, it is necessary to do so by means ofa full-scale vessel appropriately equipped with stabilizing tanks. It istherefore evident that demonstrations cannot presently be made in aneconomical and readily available manner. Furthermore, in actual on-boarddemonstrations, it is difficult to demonstrate the difference betweenstabilized and nonstabilized modes of operation. It is toward the goalof providing an economical and readily available means for demonstratingthe effectiveness of the passive tank stabilization system which thepresent invention is directed.

SUMMARY OF THE INVENTION The present invention relates to a device forvisually displaying the operation of a passive tank stabilizer. It issmall and lightweight and can therefore readily be carried by hand. Inone mode of its operation, demonstrative of the unstabilized state, itoscillates for long periods of time until frictional forces overcome theoscillatory forces and cause the oscillations to cease. When, however,the device is in its second mode of operation, demon strative of thestabilized state, oscillatory motion imparted to the device by externalforces is readily quenched. Thus, the difference between the stabilizedand the unstabilized modes of operation is readily displayed, and,consequently, the effectiveness of the passive tank stabiliizationsystem is dramatically demonstrated.

Accordingly, it is one object of the invention to provide a device whichreadily illustrates the operation of a passive tank stabilizationsystem.

It is another object of the invention to provide a device for readily,economically, and in a compact form, illustrating the differences inoperation between a stabilized and an unstabilized system.

In view of its small size, and in view of the low manufacturing costsassociated therewith, the device of the present invention can readily bedistributed by manufacturers of stabilization systems for purposes ofadvertising. Accordingly, it is another object of the inven- PatentedFeb. 23, 1971 ice tion to provide a small and inexpensive device foradvertising and, at the same time, displaying a passive tankstabilization system.

In view of its small size, its low cost of manufacture and thesurprising results its portrays, the present invention makes for aneconomical, effective and conversational paper-weight. Accordingly, itis another object of the invention to provide a paper-weight incombination with an amusement device. For purposes of providing a toy oramusement device, the device should be made of a non-transparentmaterial. Thus, the difference between the first and second modes ofoperation is mystically portrayed.

Since the device of the present invention is inexpensive to manufactureand is small and lightweight, it can be quite effective in thestabilization of toy boats. Therefore, it is still a further object ofthe invention to provide a system for stabilizing toy boats. I Thepresent invention depends, for its operation, upon the basic principleof operation of the passive tank stabilizer. This principle is that if amass moves 180 out of phase with a parent device, the parent device canbe made to rock for long periods of time. When, however, the mass ismade to move out of phase with the movement of the parent device, themass serves to stabilize the parent device and therefore to quickly dampany rocking movement therein.

While in a preferred embodiment, the invention is shown as relying uponthe operation of a liquid, it should be noted that any flowingstabilizing mass could be used. For instance, in one mode of operation,a ball could be fixed in position, thus demonstrating the unstabilizedmode; in the second mode of operation, the ball could move 90 out ofphase with the device, thus demonstrating the stabilized mode.

Also, while the device is shown as comprising a central body region witha pair of appended rocker members, it should be noted that the devicemay be manufactured with a unitary body forming a pair of rockersurfaces.

Other objects of the invention, as well as many of the attendantadvantages thereof, will become more readily apparent when reference ismade to the following description taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view of theapparatus of the present invention:

FIG. 2 is a side view of the invention shown in FIG. 1;

FIG. 3 is a front view of the invention with its front plate removed andin its stabilized mode of operation;

FIG. 4 is a front view of the invention with its front plate removed andin its unstabliized mode of operation;

FIG. 5 is a cross-sectional view through line 55 of FIG. 3.

FIG. 6 is a cross-sectional view through line 66 of FIG. 3;

FIG. 7 is a cross-sectional view through line 7-7 of FIG. 4; and

FIG. 8 is a cross-sectional view through line 8-8 of FIG. 4.

DETAILED DESCRIPTION OF THE INVENTION With reference first to FIGS. 1and 2, the device of the persent invention is shown generally at 10. Thedisplay device 10 comprises a first rocker member 12 and a second rockermember 14, each being of an arcuate shape. Intermediate the rockermembers 12 and 14 is a central body region 16 which, as is seen best inFIG. 2, houses a stabilizing mass in the form of a body of liquid 18.The central body region 16 is in the form of a chamber which is definedby a pair of side walls 38, a pair of end walls 40, a first floor member'42 which is associated with the unstabilized mode of operation and asecond floor member 44 which is associated with the stabilized mode ofoperation. Attached to one of the side walls 38 is a plate 20 whichconveniently serves as a means for displaying any name, trademark,decoration, or advertisement.

With reference now to FIGS. 3, 5, and 6, depicting the apparatus of thepresent invention when in its stabilized mode of operation, the deviceis shown resting on its rocker member 12. In this position, the liquid18 housed within the chamber 16 can be viewed as occupying threeseparate volumes. These separate volumes are defined by a centralchamber 22 and a pair of end chambers 24. Serving to define the threeindividual chambers is a transparent block 26 and a pair of transparentstrips 28. The block 26 and strips 28 are shown to extend from the wall44 of the central chamber 16 nearest the rocker member 12 to the wall 42of the central chamber 16 nearest the rocker member 14. However, theblock 26 and the strips 28 may be constructed to extend toward the wall42 only an amount necessary to ensure that the liquid 16 never passesthereabove when the device 12 rests on the rocker member 12.

It will be noted that when the article is resting on its rocker member12, the liquid 18 is housed in what may be termed a C-tank. This canbest be seen in FIG. 5. It should also be noted that when the liquid 18is passing from one end chamber 24 to the other, it passes through apair of nozzles 30, each nozzle being formed by a portion of the block26 and a respective strip 28. For best results, the liquid level in thetank should be slightly higher than that necessary for resonance betweenthe liquid oscillations and the natural frequency of the device.

Reference is now directed to FIG. 4 and its associated sectional views,FIGS. 7 and 8, each showing the article of the present invention in itsnon-stabilized position of operation. When the article rests on itsrocker member 14, the liquid 18 housed within the central chamber 16 canbe said to occupy a plurality of volumes. These volumes are defined bychambers 32 which are formed by a plurality of parallel and spacedelements 34 extending from the wall 42 of the chamber 16 upwardly andtoward the wall 44 an extent suflicient to ensure that the liquid 18does not pass thereover. While the elements 34 serve to define thechambers 32, it should be noted that the elements do not entirelyisolate one chamber from its neighbors. This is best seen in FIG. 8.More particularly, each element 34 abuts the Wall 42 over a substantialportion of said wall. However, the extreme ends of each element 34 isbevelled in such a manner as to provide passages 36 for the flow ofliquid from one chamber 32 to its neighbor chambers. In this way, aconstant list is avoided.

The operation of the device 10 forming the present in vention is firstdescribed with reference to the unstabilized condition shown in FIG. 4,there then following a description of the invention with reference tothe stabilized condition shown in FIG. 3.

With reference again to FIG. 4, the device 10 is shown resting on itsrocker member 14. By an external force, the device is rolled along therocker until it experiences a substantial list relative to its steadystate position shown in this figure. When released, the device 10 rocksto and fro on the rocker member 14, and only after the frictional forcesassociated with such rocking overcome the motion, does the devicestabilize. This stabilization occurs after approximately twenty-fiveoscillations.

When, however, the device 10 is in the position indicated in FIG. 3,stabilization occurs rapidly. To demonstrate the rapidstabilizationbrought about by passive tank stabilization systems, the device 10 isrolled along its rocker member 12 until it experiences a substantiallist. The device is then released. Due to the effect of the liquid inthe chamber 16, and more particularly in the C-tank effective in thismode of operation, the device rocks along its rocker member 12 for onlya short period of time. The rocking is quieted by an action similar tothat present in a ship equipped with a passive tank stabilization systemand is quieted after approximately two oscillations.

Thus, when comparing the operation in its unstabilized and stabilizedmodes of operation, the device 10 rocks more than ten times as long inits unstabilized state as it does in its stabilized state. It istherefore readily apparent that the device of the present invention isquite dramatic in illustrating the eifectiveness of a passivestabilization system.

It should be noted that the device of the present invention is intendedmerely to illustrate the effectiveness of a stabilization system.Therefore, it is to be understood that the mode of operation termed theunstabilized mode ist not necessarily representative of an unstabilizedvessel, for instance. Rather, the elements 34 are inserted in the device10 only to cause the device to uncontrollably rock in its unstabilizedmode. On the other hand, the configu ration of the C-tank eifective inthe stabilized mode of operation is, in fact, a tank that can beincorporated in an ocean going vessel. In view of the above, it shouldbe noted that the unstabilized mode of operation may be perfected bymeans other than the elements 34; likewise, the stabilized mode may beperfected by means other than the C-tank shown and described.

As noted above, the device of the present invention has been describedwith reference to a preferred embodiment. It is the intent, however,that the invention not be limited thereto, since many subsitutions andmodificaions will become apparent to those skilled in the art, but belimited only as defined in the appended claims.

What is claimed is:

1. A device, having two modes of operation, for demonstrating theoperation of a passive tank stabilization system, and comprising: aclosed chamber; a stabilizing mass partially filling said closed chamberfor stabilizing said device when in its first mode of operation; andmeans for preventing said stabilizing mass from stabilizing said devicewhen in its second mode of operation.

2. The invention as recited in claim 1, wherein said chamber includesfirst phase means associated with said first mode of operation formaintaining the phase between the position of the device and theposition of the stabilizing mass near and second phase means associatedwith said second mode of operation for maintaining the phase between theposition of the device and the position of the stabilizing mass near 3.The device of claim 1 wherein said stabilizing mass is a liquid andwherein said first and second phase means comprise first and secondtanks for housing said liquid when said device is in its first andsecond mode of opera tion, respectively.

4. The invention as recited in claim 3 wherein said second phase meansserves to substantially eliminate the flow of liquid from one end to theother of said second tank.

5. The invention of claim 3 wherein said second phase means is formed bya plurality of elements parallel to and spaced from one another, saidelements being fixedly secured to one wall of said closed chamber, saidone wall serving as the bottom of said second tank when the device is inits second mode of operation.

6. The invention as set forth in claim 5 wherein said elements extendfrom said one wall of said chamber an amount sufficient to ensure thatthe liquid housed in said chamber does not pass over said elements whensaid demonstration device is in its second mode of operation.

7. The invention as recited in claim 5, wherein said elements have amaximum width corresponding to the internal width of said chamber andwherein said elements are fixedly secured to said one wall of saidchamber for only a portion of their width to allow for slightcommunication past each element.

8. The invention as recited in claim 7 wherein said elements are securedto said one wall in such a manner that small passages are formed betweensaid one wall and each of said elements at the extremities of each ofsaid elements.

9. The invention as recited in claim 3 wherein said first phase means isdefined by a block of material secured to a side wall of said chamber,wherein said block is positioned centrally with respect to the length ofsaid chamber.

10. The invention as set forth in claim 9, and further comprising: firstand second strips of material fixedly attached to a second side wall ofsaid chamber opposite the wall serving to support said block ofmaterial, said first and second strips being positioned, respectively,adjacent the extremities of said block and each forming a nozzle withthe respective extremity of said block.

11. The invention as recited in claim 10 wherein said block and saidfirst and second strips extend from the wall of said chamber serving asthe bottom of said first tank when the device is in its first mode ofoperation, an amount suflicient to ensure that the liquid housed in saidchamber cannot pass over said block and strips when said demonstrationdevice is in its first mode of operation.

12. The invention as defined in claim 1 wherein said device is of atransparent material.

13. The invention as defined in claim 1 wherein said device is of anon-transparent material.

14. The invention as defined in claim 5 wherein said first phase meansis defined by a block of material secured to a side wall of saidchamber, wherein said block is positioned centrally with respect to thelength of said chamber.

15. The invention as described in claim 14, and further comprising firstand second strips of material fixedly attached to the side wall of saidchamber opposite the side wall serving to support said block ofmaterial, said first and second strips being position, respectively,adjacent the extremities of said block and each forming a nozzle withthe respective extremity of the said block.

16. The device of claim 1, wherein said device is of unitaryconstruction.

17. The invention as recited in claim 1, and further comprising firstmeans for rocking said device when in its first mode of operation andsecond means for rocking said device when in its second mode ofoperation.

18. A device for demonstrating the operation of a passive tankstabilization system, and comprising: a main body portion forming aclosed chamber partially filled with a stabilizing mass; first meanspositioned adjacent one wall of said main body portion for rocking saiddemonstration device; second means adjacent an opposite wall of saidmain body portion for rocking said demonstration device; first tankmeans within said main body portion operative only when the device ispositioned on said first rocker means, said first tank means serving,when operative, to control the flow of said stabilizing mass in saidmain body portion in such a manner that an initial oscillation impartedto the demonstration device is sustained for a long period of time; andsecond tank means within said main body portion operative only when thedevice is positioned on said second rocker means, said second tank meansserving, when operative, to control the flow of said stabilizing mass insaid main body portion in such a manner that an initial oscillationimparted to the demonstration device is rapidly quieted.

19. The device as described in claim 18, wherein said first tank meanscomprises a plurality of chambers operative when said device ispositioned on said first rocker means and wherein said chambers areformed on the wall of said main body portion adjacent said first rockermeans.

20. The invention of claim 19, wherein said chambers of said first tankmeans are formed by means of a plural-ity of elements parallel to andspaced from one another, said elements being fixedly secured to the wallof said main body portion adjacent said first rocker means.

21. The invention as recited in claim 18, wherein said second tank meanscomprise a plurality of chambers adjacent said second rocker means.

22. The invention as recited in claim 21, wherein said chambers of saidsecond tank means are defined by means of a block of material secured toone wall of said main body portion, wherein said block extends betweensaid first and said second rocker means, and wherein said block ispositioned centrally with respect to the length of said main bodyportion.

23. The invention as set forth in claim 22, and further comprising:first and second strips of material fixedly attached to the wall of saidmain body portion opposite the wall serving to support said block means,said first and second strips being positioned, respectively, adjacentthe extremities of said block means and each forming a nozzle with therespective extremity of said block means.

24. The invention as defined in claim 20, wherein said second tank meanscomprises a plurality of chambers adjacent said second rocker means,wherein said chambers of said second tank means are defined by means ofa block of material secured to one wall of said main body portion,wherein said block extends between said first and said second rockermeans, and wherein said block is positioned centrally with respect tothe length of said main body portion.

25. The invention as described in claim 24, and further comprising firstand second strips of material fixedly attached to the wall of said mainbody portion opposite the wall serving to support said block means, saidfirst and second strips being positioned, respectively, adja cent theextremities of said block means and each forming a nozzle with therespective extremity of said block means.

References Cited FOREIGN PATENTS 2,700,228 1/1955 Fainman 35-502,971,270 2/ 1961 Hasty 35-19X HARLAND S. SKOGQUIST, Primary ExaminerUS. Cl. X.R. 46-41

